IBM 560 - Manual (Page 62)

Figure 3-1. PCMCIA Standards and Specifications
Standards and Specifications Characteristics
PCMCIA Card Standard Release 2.0 or 2.1
PCMCIA Socket Services Interface Specifications Release 2.0 or 2.1
PCMCIA Card Services Interface Specifications Release 2.0 or 2.1
PC Card Physical Configuration Type II and Type III
Supported voltage 5.0 V dc only
3-8 ThinkPad 560/560E Subsystems